Kardos’ Fall: Kardos is both the entities of the sun and the god of the sun, and also the patron god of humankind. They ere rulers of all of the world, the other races were subservient to them and they had all power of the land.
They then grew cocky, and thought, ‘If we are so powerful to have the whole world at our command, why do we not go to the land of the gods, surely we deserve to be with the rulers of all.’ So they started building a giant stairway/tower (theories vary) to the sky.
The closer the humans climbed to the sky, the hotter and brighter the sun became, emboldened by humanities successes. The other gods came to Kardos and pleaded with him to stop his followers, as the sun would burn the whole world should they reach the sky.
Kardos laughed, and thought them jealous of his power and bade the humans climb higher to prove their might. In order to save all of life on Iyrida, the gods threw Kardos from the heavens.
The blast from him impacting the earth destroyed the tower and it flew into the sky where the gods created it as a shield in front of the sun, which we now call Kozha, the Guardian. With their tower destroyed, their celestial guardian hidden, and their god fallen to the ground, the humans fled underground, and so they have stayed.